The Owls confirmed the move on their official website two hours before the transfer window closed, but did not disclose the length of the deal, or the fee.

The Boro Academy graduate spent much of last season on loan at Preston where he scored four goals in 36 appearances.

Reach was an unused substitute in Middlesbrough's goalless draw with West Brom at the weekend, but has not featured in any of the Teesside club's opening four matches this term.

The 23-year-old told Wednesday's official website: "I'm really pleased. It's been a whirlwind day and I went into it not really knowing what was going to happen.

"I trained with Boro and then as soon as I was told of the interest from Sheffield Wednesday, I wanted to get straight down here.

"Everyone knows what the club achieved last season and everyone knows what they want to achieve this season. I want to be part of that."

On a busy day of transfer activity at the Riverside, highly-rated central-back Dael Fry, 19, pledged his long-term future to Boro by signing a new five-year contract, then joined Rotherham United on a season-long loan.

And 30-year-old defender Alex Baptiste joined Preston North End on a season-long loan, linking up with his former Blackpool manager Simon Grayson at Deepdale.